.bl-div {
  position: relative;
  margin: auto;
  line-height: 20px;
  text-align: center;
  color: #fff;
  border: 2px solid gold;
  border-radius: 10px;
  cursor: pointer;
}
.bl-div:hover {
  filter: contrast(1.1);
}
.bl-div:active {
  filter: contrast(0.9);
}
.bl-div::before, .bl-div::after {
  content: "";
  position: absolute;
  top: -10px;
  left: -10px;
  right: -10px;
  bottom: -10px;
  border: 2px solid gold;
  transition: all 0.5s;
  -webkit-animation: clippath 3s infinite linear;
          animation: clippath 3s infinite linear;
  border-radius: 10px;
}
.bl-div::after {
  -webkit-animation: clippath 3s infinite -1.5s linear;
          animation: clippath 3s infinite -1.5s linear;
}

@-webkit-keyframes clippath {
  0%, 100% {
    -webkit-clip-path: inset(0 0 98% 0);
            clip-path: inset(0 0 98% 0);
  }
  25% {
    -webkit-clip-path: inset(0 98% 0 0);
            clip-path: inset(0 98% 0 0);
  }
  50% {
    -webkit-clip-path: inset(98% 0 0 0);
            clip-path: inset(98% 0 0 0);
  }
  75% {
    -webkit-clip-path: inset(0 0 0 98%);
            clip-path: inset(0 0 0 98%);
  }
}

@keyframes clippath {
  0%, 100% {
    -webkit-clip-path: inset(0 0 98% 0);
            clip-path: inset(0 0 98% 0);
  }
  25% {
    -webkit-clip-path: inset(0 98% 0 0);
            clip-path: inset(0 98% 0 0);
  }
  50% {
    -webkit-clip-path: inset(98% 0 0 0);
            clip-path: inset(98% 0 0 0);
  }
  75% {
    -webkit-clip-path: inset(0 0 0 98%);
            clip-path: inset(0 0 0 98%);
  }
}
.bg::before {
  background: rgba(255, 215, 0, 0.5);
}